Climate change may boost rain in Kenyan river basin - scientists

ROME, Dec 19 (Thomson Reuters Foundation) - Kenya’s Tana River Basin, a major source of hydroelectric power, food and fresh water, may see its annual rainfall increase as much as 43 percent by the end of the century because of climate change, scientists said on Tuesday.

The river basin, stretching from the centre to the east of the country, is home to 8 million people. It supplies 70 percent of Kenya’s hydro-power, and 80 percent of Nairobi’s drinking water, according to UN Environment.

Scientists say the Tana River Basin, which has experienced drought over the past few years, is likely to get wetter this century, although they do not know for certain by how much.

If that happens, farmers may be able to grow more crops, thanks to a larger water supply, and the region could produce more electricity, scientists from the International Water Management Institute (IWMI) said in a report.

The downside is that more water raises the risk of flooding, they added.

A wetter climate in the basin will affect decisions on irrigation and infrastructure like dams, said James Dalton of the International Union for Conservation of Nature, which leads the “WISE-UP to Climate” project that produced the report.

Currently the basin has five major dams, with several more planned, he noted.

“Knowing in clear technical terms how climate change might affect the hydrology of the basin and, hence, the performance of these costly investments is extremely important for water managers and policy makers,” he said in a statement.

The researchers used six climate change models, simulating different levels of planet-warming greenhouse gas emissions.

Report co-author Matthew McCartney of IWMI said the findings were largely in line with previous studies, including from the Intergovernmental Panel on Climate Change.

"This is important, since modelling of climate change impacts on water resources is not an exact science and large uncertainties remain, which can lead to highly variable conclusions," he added. (Reporting by Alex Whiting @Alexwhi, editing by Megan Rowling; Please credit the Thomson Reuters Foundation, the charitable arm of Thomson Reuters, that covers humanitarian news, climate change, resilience, women's rights, trafficking and property rights. Visit news.trust.org/climate)